A plastic body and cap of the type to which the present invention relates is generally an injection-molded plastic container that has a plastic cap adapted to seal the body closed with a leakproof seal. Such body and cap are, for example, the vial that may be used to collect a test sample of milk or urine, or to ship sterile water, or other types of containers having caps. The cap is typically integrally connected to the body.
U.S. Pat. No. 4,783,056 relates to a method for accomplishing sealing of a cap onto a vial including a mold with several moving parts in which the vial may be molded and sealed in the same apparatus. This method of forming and sealing an aseptic vial eliminate the additional step of sealing the vial under aseptic conditions because the sealing is done directly in the mold while the vial is still hot enough to maintain the necessary pliability and sterility of the vial. However, this method requires the use of a mold which has moving parts for closing and sealing the cap on the vial and does not easily facilitate the transfer of a liquid to the container prior to sealing.
U.S. Pat. No. 5,723,085 relates to a process and apparatus for making a leakproof cap and body assembly. This process discloses a method of injecting a molten material into a mold cavity, separating the mold cavity, engaging at least the body with a robotic arm while the assembly is in the mold and moving the cap and body assembly with the robotic arm into a capping device while the body and cap are at a temperature at which the material is not fully set. The body is then sealed by moving the cap into engagement with the body to form a leakproof seal.